Techniques used for decoding image bitstreams where the resultant image is to be cropped for display can include entropy decoding an entire encoded image in a first pass operation. Then in a second pass operation, steps to dequantize, inverse discrete cosine transform (DCT), upsample and color convert pixels to generate an image are performed. Finally, in a third operation, the decoded image is cropped. Some techniques can perform the cropping operation during the second pass operation.
Dequantizing, inverse DCT transforming, upsampling and color converting pixels can be processor intensive operations.